HTB - Sizzle

Machine Info
Sizzle is an insane difficulty Windows box with an Active Directory environment. A writable directory in an SMB share allows to steal NTLM hashes which can be cracked to access the Certificate Services Portal. A self signed certificate can be created using the CA and used for PSRemoting. A SPN associated with a user allows a kerberoast attack on the box. The user is found to have Replication rights which can be abused to get Administrator hashes via DCSync.
Enumeration
Scope
IP Address: 10.10.10.103
Nmap Scan
Update hosts file with domain name, FQDN and computer name
DNS Enumeration
Zone transfer failed
RPC Enumeration
KERBEROS Enumeration
I can't get any user from bruting kerberos.
LDAP Enumeration
No thing also from ldap
HTTP & HTTPS Enumeration
subdomain enumeration
Both links http://htb.local/ & https://htb.local/ lead to the same page

From wappalyzer extension, the webapp runs with ASP.NET technology on IIS web server

Since we are dealing with IIS web server, I will try fuzzing for directories with ISS.fuzz wordlist
/certsrv requires http authentication

/certenroll gives Access is denied
I can say that the machine has Certificate authority installed on the system.

SMB Enumeration
Anonymous login is enabled along with guest account.
I will mount Department Shares locally for easy exploring
Shell as amanda
ZZ_ARCHIVE has several files & Users has users' folders
I will try to write a file on each directory and see if I have write access to one of them.
I will then search for file.txt and see if It was created successfully in any directory
So, I have Write Access to ZZ_ARCHIVE & Public folders , I will try to put .scf or .lnk file to steal NTLMv2 hash if any user enter the shared folder.
The structure of the file looks like this.
Putting the file to the share.
I will start Responder to listen for incoming connection
Get a hash

Starting hashcat to crack the hash
Cracked successfully :)

Verify with cme
Although the credentials are valid, I can't access the machine with winRM
I will continue to enumerate the machine with this credentials including
Share Access
Bloodhound Collector
/certsrvauthentication
This time I have read access on CertEnroll share
When viewing the share content, I find interesting files
Download them all
I will make Enumerate share access done in my notes and switch to collect data with bloodhound.py for further enumeration and go to /certsrv page
I Uploaded the zip file to bloodhound and go to /certsrv
After Authenticated to webapp, It leads me to this page.

I will click on Request a Certificate

Click on advanced certificate request

It asks for Certificate signing request .csr which can be signed with a private key, and I don't have one, So I will generate my private key and sign a .csr file with it.
To login to the machine, I need to have certificate signed from
Certificate Authority (CA)of the domain along with the private key with which the certificate singing request was signed.
Generate the key and csr files.
Paste the csr

Click on Download Certificate!

I will use
evil-winrmwith the following options and enter passphrase when promoted:-Senable SSL-caccept Certificate file-kaccept private key
From impacket toolkit, I use GetUserSPN to find account with Service Prinicpal Names that can be kerberoasted
When I tried to perform kerberoasting attack from Linux, it failed, So I will attempt it from windows.
When I tried to upload any tool to the box and execute it, it failed, So there might be something preventing me.
We are in Constrained Language modelCLM
Also, after I Queried AppLocker policy, I found that I can run programs in tmp folder
Shell as mrlky
Performing kerberoasting against mrlky user with Rubeus.exe

Cracked :)

I will then upload RunasCs.exe to the machine to get a shell as mrkly
Receive the connection with nc.
Get user flag
User Flag: b31ca0c7a5bcc77a55xxxxxxxxxxxxxx
Shell as Administrator
From bloodhound, User Mlky has DCync rights, I can take over the domain by dumping ntds database.

OR with secretsdump.py
Access the machine with psexec.py
Get administrator flag
Root Flag: c3d8011c9688feccaxxxxxxxxxxxxxxxx
Last updated